Butterfly sighting

Jul 13 2010

Edgar Spalding

Location: Biocore Prairie
Dane County

This female black swallowtail showed no cell-end spot, which threw me for a loop but didn't faze the two males that pursued her high into the air for at 200 yards before she dropped fast down into the prairie. I thought the cell-end spot was a surefire underside field mark, but I guess it can be absent.